body {
  margin: 0;
  font-family: Arial;
  background: #0b0b0f;
  color: white;
  text-align: center;
}

header {
  background: linear-gradient(135deg,#87CEEB,#5FB9E0);
  padding: 20px;
  font-size: 24px;
  font-weight: bold;
}

.container {
  padding: 20px;
}

.video-box {
  background: #000;
  border-radius: 15px;
  overflow: hidden;
}

video {
  width: 100%;
}

.card {
  margin-top: 30px;
  padding: 20px;
  border-radius: 20px;
  background: #111;
  box-shadow: 0 0 25px rgba(0,255,150,0.2);
}

.install-btn {
  margin-top: 20px;
  padding: 15px;
  border-radius: 30px;
  background: linear-gradient(90deg,#00ff88,#00cc66);
  color: white;
  font-size: 18px;
  border: none;
}